The patient is severely ill. Temperature is 39°C (102.2°F). Shortly after admission, she requires intubation with ventilatory support. Hypotension, acrocyanosis, and an ecchymotic rash consistent with purpura fulminans (A) rapidly develop.
Physical examination reveals an abrasion in the second web space of the left hand (B), which resulted from a dog bite at work 72 hours earlier. The white blood cell count is 1000/μL; platelet count, 8000/μL; hemoglobin level, 8.9 g/dL; and blood urea nitrogen and creatinine levels are 22 mg/dL and 3.3 mg/dL, respectively. Arterial blood gases are representative of a compensated anion gap metabolic acidemia (with a pH of 7.20).
Blood cultures are obtained. Empiric therapy with vancomycin, ceftriaxone, and penicillin is initiated. A buffy coat specimen demonstrates fusiform-like gramnegative bacilli (C). Skin biopsy specimen reveals smallvessel fibrin-platelet thrombi without organisms.
The patient’s condition deteriorates, and she becomes unresponsive. A CT scan of the head shows findings consistent with subarachnoid and intraventricular hemorrhages. She dies within 48 hours.
What caused this patient’s rapid deterioration?
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